Instead of taking about her tumultuous personal life or her children, Garner shared a shockingly intimate story about the difficulties involved in fitting into her curve-hugging black dress for this year's Academy Awards.

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After Fallon complimented Garner on her stunning red carpet ensemble, Garner went into explicit detail about how the dress was made specifically for her, and wound up sharing more than anyone was expecting.

"Do you know how they made it?" Garner asked, pointing to a photo of the custom Versace gown. "See how I have a waist right there? I don't have one in real life anymore."

"What they do is, the move your organs around," the 43-year-old mother of three explained with a laugh. According to the star, she was placed into a metal corset by two men "and the next thing I know my ribs were compressed."

"It was not like [Spanx], it is so intense," she stressed. "It's not like Scarlett O'Hara. There's metal inside it. And these people just kind of move your ribs and they move your liver out to the side and they pop you in."

She went on to explain that, to keep everything in place, she had to step into a partial body-suit that was basically a very tight, very awkward thong. And it was this bizarre body suit that would lead to one insanely awkward situation.

During the ceremony, Garner realized that she had to go to the bathroom, which the actress related to the situation some brides experience when having to go the bathroom immediately after getting their wedding dress on.

Luckily, she was attending the ceremony with one of her best friends, who suddenly found herself tasked with helping Garner use the restroom.

"We go into the bathroom, because [I know] she's going to have to hold something up," Garner said, referring to the hem of her custom gown. But it turns out the hardest part of the entire operation wouldn't be the dress, but the skin-tight bodysuit.

"The connection of the body-suit, because it had a hook-and-eye situation, was in an intimate position," Garner said delicately while Fallon got visible nervous about the direction her anecdote was taking. "It was like… in my vagine."

"Okay, okay, yeah, yeah, yeah," Fallon stuttered, trying to get the story back on to family-friendly ground. Unfortunately, his efforts were in vain. "We all have a mental photo, we're good."

"So I couldn't reach it," Garner continued, undeterred. "I said to my friend, 'I don't know what's gonna happen, but I think you've got to get this.' She's a good friend. She said, 'If this has to be done, it had to be done, but listen, I want you to give it a good college try.'"

As the actress explained during the course of her surprisingly candid tale, "It's not pretty, but I just feel like you should know the truth about these things."